ULTRACENTRIFUGAL STUDIES OF SYNOVIAL FLUID LIPOPROTEINS TABLE I Clivtical data on patients studied Differential PMN * Wester - Latex Leuko - Round gren fixation Patient Age Sex Diagnosis Joint Mucin cytes cells ESRt

Studies on the synovial fluid lipoproteins were initiated several years ago. In 1953 Ropes and Bauer (1) reported on the cholesterol content of joint fluid from patients with rheumatoid arthritis. Subsequently Schmid and MacNair (2, 3) noted that when referred to the same amount of protein rather than volume of fluid, the lipoprotein content of pathological and pooled postmortem synovial fluids was very similar and amounted to approximately two-thirds of the corresponding value of normal human serum. The ratio of f8to a-lipoproteins of certain fluids from patients with rheumatoid arthritis, however, was essentially the same as that of the patient's serum. Recently Chung, Shanahan, and Brown (4) and Bole (5) studied the lipid content of the different classes of synovial fluids, as did Schur and Sandson (6), who stated that 83-lipoprotein was markedly decreased as compared to normal serum. Since most of the fractionation procedures used separated the serum and synovial fluid lipoproteins into only two groups, the reported results led to a very rough description of these substances. The use of ultracentrifugal techniques would permit characterization of essentially all classes of lipoproteins of serum and synovial fluid and the detection of small differences that might be found in various lipoprotein classes. The present study therefore was undertaken a) to assess analytical ultracentrifugation methodology in the analysis of synovial fluid lipoproteins, b) to compare synovial fluid and serum lipoprotein levels in a given patient, and c) to determine whether different